Use of Ash from Coffee Wood into Clayey Ceramic

Abstract

This work has as its objective to evaluate effect of the incorporation of an ash, obtained from burning wood from coffee plant, in the physical and mechanical properties of incorporated clayey ceramic. The ash has undergone characterization tests by the techniques of XRF, DTA / TG and XRD. Formulations were prepared with 5, 10, 20 and 30 wt% of ash incorporated into clay bodies that were then homogenized, dried and finally moistened. Rectangular test specimens were prepared by uniaxial pressing in a steel mold at 20 MPa, followed by firing at 700 °C. The fired ceramics were subjected to physical and mechanical tests for determining the bulk density, linear shrinkage, water absorption and tensile strength. The results indicate that the ash is composed predominantly of calcium, magnesium and potassium oxides. The incorporation of ash up to 20 wt% decreased the water absorption and notably increased the ceramic mechanical strength in the temperature investigated.